Coil spring winding machine

ABSTRACT

A precisely operating coil spring winding machine of the type which twists the wire before coiling it the machine is of particularly compact construction, and requires no rotatable reel for the supply bale of wire. The winding machine has a winding mandrel which is not only rotatable about its axis but is additionally rotatable about a second axis at rightangles to its longitudinal axis, the second axis intersecting the axis of the wire at its point of run-on where the incoming spring wire first touches the periphery of the winding mandrel, and being located parallel with the tangent on the winding mandrel at the run-on point. It is expedient to use a drivable frame which is rotatable about the aforesaid axis and on which the winding mandrel is disposed in rotatable fashion.

United States Patent v [191 Huhnen Apr. 30, 1974 22 Filed:

[ COIL SPRING WINDING MACHINE [76] Inventor: Joachim Huhnen, Blankensteinstr.

[30] Foreign Application Priority Data Feb. 28, 1972 Germany 2209340 [52] US. Cl. 72/142, 72/65, 72/137,

' 72/143 [51] Int. Cl 132" 3/04 [58] Field of Search 72/143, 142, 137, 130, I 72/64, 65; 57/66 [56] References Cited UNITED STATES PATENTS 3,570,291 3/1971 Shiguma 72/142 3,039,706 6/1962 Toth et al. 72/143 2,868,268 1/1959 Lewis et a1... 2,373,427 4/1945 Stickney 72/143 1,579,325 4/1926 Ka'seberg 72/143 1,368,297 *2/1921 Sleeper 727143 FOREIGN PATENTS OR APPLICATIONS 933,861 9/1955 Germany '1 Primary ExaminerCharles W. Lanham Assistant Examiner-James R. Duzan Attorney, Agent, or FirmArthur O. Klein [5 7] ABSTRACT A precisely operating coil spring winding machine of the type which twists the wire before coiling it the machine is of particularly compact construction, and requires no rotatable reel for the supply bale of wire. The winding machine has a winding mandrel which is not only rotatable about its axis but is additionally rotatable about a second axis at rightangles to its longitudinal axis, the second axis intersecting the axis of the wire at its point of run-on where the incoming spring wire first touches the periphery of the winding mandrel, and being located parallel with the tangent on the winding mandrel at the run-on point. It is expedient to use a drivable frame which is rotatable about the aforesaid axis and on which the winding mandrel is disposed in rotatable fashion.

12 Claims, 4 Drawing Figures COIL SPRING WINDING MACHINE The invention relates to a winding machine for producing coil springs, with a winding mandrel rotatable about its longitudinal axis and at the same time displaceable in an axial direction and on which the free end of a spring wire can be firmly clamped.

In the case of the known winding machines of this type, the spring wire is regularly wound onto the mandrel in an untwisted state. However, winding machines are already known, for example in German Patent Specification No. 933,861 and United States Patent Specification No. 3,570,29l, in which the spring wire, before it is wound, is elastically twisted as for as its shear elasticity limit so that the torsion additionally occurring in the wire during winding plastically deforms the wire, which is why the completed spring has a substantially higher initial tension wound into it. For the purpose of elastic twisting, the machine described in German Patent Specification No. 933,861 has a twisting apparatus which receives the spring wire supplied, for example, from a bale of wire, which can then be disposed at the greatest possible distance from the winding mandrel, so that the portion of wire located inbetween suffers only an elastic'twisting and has not already been previously subjected to plastic deformation- The considerable distance'between the bale of wire'and the winding mandrel, in some circumstances, gives rise to space problems which are avoided by the winding machine according to US. Pat. No. 3,570,291, because in such latter machine the bale of wire is disposed on a reel which is mounted to rotate both about its axis of symmetry as well as about a diameter in line with the axis of the portion of wire located between two feed rolls and the winding mandrel. The difficulties which arise in practice with such apparatus are considerable,

the main problems being caused by the considerable.

mass of the reel with the bale of wire thereon and the lack of regularity in its distribution on the reel.

The present invention provides a precisely operating winding machine which is of particularly compact construction, which requires no rotatable reel for the bale of wire, and which overcomes the difficulties encountered in the machines described at the outset hereinabove. The rotatable winding mandrel of the machine of the invention is additionally rotatable about an axis at right angles to its longitudinal axis, such axis intersecting the axis of the wire at its point of run-on, at which the incoming spring wire first touches the periphery of the winding mandrel, and is located parallel with the tangent on the winding mandrel at the run-on point. It is expedient to use a drivable frame which is rotatable about the aforesaid axis and on which the winding mandrel is disposed in rotatable fashion.

Since the winding mandrel, according to the invention, does not only need to cope with winding on the spring wire, but additionally takes over the twisting thereof, it is possible to supply for the bale of wire a reel rotatable only about its axis of symmetry; such reel can be disposed in'the immediate vicinity of the winding mandrel, so'that space can be saved.

The invention will be explained in greater detail hereinafter with reference to four forms of embodiment of the sinding machine according to the invention, which are illustrated by the attached drawings.

IN THE DRAWINGS FIG. 1 is a schematic view in longitudinal section of a first embodiment of the machine in accordance with the invention, certain of the parts being broken away for clarity of illustration; and

FIGS. 2, 3, and 4 are fragmentary views similar to FIG. 1 of three further embodiments of the machine of the invention, respectively.

In FIGS. 2, 3 and 4 parts which are the same as or similar to those of FIG. 1 are designated by the same reference characters.

In all four embodiments shown, twisting of a spring wire 29 is achieved by constantly whirling a winding mandrel about the point on the axis of the wire at which the wire 29 runs onto the winding mandrel. A guide sleeve 34 for wire 29, a knife 32 for cutting off the wire, and feed rolls 35, for clamping the wire in nonrotatable manner are provided. On the winding mandrel, there is provided a clamping arrangement 30 which grips the leading end of the wire on the mandrel.

I The whirling head 60 of the embodiment of the machine shown in FIG. 1 has a U-shaped frame 61 journalled on a fixed stub shaft 62, there being a bevel gear 66 fixedly mounted on element 62. Mounted in the element 62 is an electric motor 63 a spur gear 64 on the driving shaft of which drives the frame 61 through a meshing gear in the direction indicated by the arrow 65. The winding mandrel 67 which carries the aforesaid clamping arrangement 30, has a portion 24 shaped in transverse section like a rod-shaped pinion, section 24 being connected in non-rotatable manner to it. The mandrel 67 is mounted on a threaded spindle 68 for rotation about its axis and simultaneous axial displacement.- The gear portion 24 is non-rotatably connected to the bevel 66 by an intermediate gearing 69 which, through a clutch 70 and a gear transmission 71, rotates the spindle 68 and thus adjusts the pinion 24 with the winding mandrel 67 radially of the head 60.

With the drive to gear wheels 71 disengaged and such gear wheels at rest, a coil spring is normally produced as follows: the wire 29 is gripped in the clamping arrangement 30 and is prevented from rotating by the pair of rollers 35. The motor 63 rotates the frame 61 substantially about the axis of the wire 29. At the same time, the intermediate gearing 69 positively drives the pinion 24 and hence the mandrel 67, which results in a relative movement with respect to the fixed threaded spindle 68, so that the gear 24 and mandrel 67 are moved radially outwardly in a helical movement. This produces a wound coil spring, the pitch of which is equal to that of the thread of spindle 68. When the gear transmission 71 is driven, which is possible by means of engagement of the clutch 70, the threaded spindle 68 is itself also rotated; the pitch of the spring is now changed positively or negatively, depending upon the direction of rotation of spindle 68.

The second embodiment shown in FIG. 2, conforms to the first embodiment (FIG. 1) except for the following: A winding mandrel 72 of modified form carries the clamping arrangement 30 and is rigidly connected to the coaxial spindle 73. This has a longitudinal groove 74 in which a spline 75 slides. The spindle 73 is screwed into an externally toothed rotatable nut 76 which is joumalled in one end portion of the frame 61 and meshes with an externally toothed clutch part 80. Likewise rotatably mounted in this end portion is a gear wheel 77 which receives the spindle 73 in a bore therethrough and which is driven by a pair of meshing gear wheels 78, a key or spline on gear wheel 77 fitting into groove 74 and imparting its rotation to the spindle 73 by means of the spline 75. The driving shaft 79 is a part of the intermediate gearing 69 shown in FIG. 1. The other part of the clutch 81 is non-rotatable but is axially displaceable on the shaft 79.

A spring is produced from the wire 29 in that the driving shaft 79, through a pair of gear wheels 78 and the gear wheel 77 with the spline 75 rotates the mandrel 72 while the mandrel, by its rotation in the nut 76, determines the pitch of the spring in known manner. This pitch is varied by a relative rotationof the nut 76 which is initiated by engaging the clutch 80, 81.

In a simplified construction, the whirling head partly shown in FIG. 2 may-also be made without the clutch parts and with a non-rotatable nut (corresponding to nut 76) for the spindle. Traction coil springs with wound-in initial tension can be produced with'such a machine if the pitch of the spindle conforms to the thickness of the wire. 7

In the embodiment according to FIG. 3, the winding mandrel 67 is mounted on a multiple-groove shaft 110 which is positively driven by meshing bevel gears 111,

7 change wheels 1 12 and also gear wheel 1 l3, and a fixed pinion'l14, when the whirling head 60 is rotated. The multiple groove shaft 110 is mounted to rotate inthe frame 61 and'is also radially displaceable independently thereof. The radial displacement takes place against the restoring force of a thrust spring 115 by the wound spring body running against guide rollers 116.

The wound spring is supported thereby on a supporting ring 133 in the form of an annular flange. At the dead center position of a crank transmission28 and during the reverse motion thereof, the guide rollers 1 16 are pivoted out in a mannersimilar to a differential transmission, or like the known adjusting devices on variable propellers, so that the completed coil spring can be withdrawn from the winding mandrel. The guide rollers 116 are pivoted out by means of a shaft 120, the

' axis of .which is at an angle tothe axis of rotation of the frame, i-.e., of its pivot 122, and points past the winding mandrel 67, in other words extends into the depth of the'plane of the drawing. The adjusting device 117 is actuated by a cam plate 124. Through the crank transmission 28, an electric motor 63 drivesa rack 125 which meshes with a pinion 1 27 and which is guided in a slide block 126. The pinion 127 drives through an overrun device, agear wheel 128 which contains this latter and gear wheel 128 in turn drives a gear wheel 137 which is located on the frame pivot 122. A cam 33 and thus the cut-off knife 32- following the guide sleeve 34, is actuated through a shaft 129.

The feed rolls 35 are driven through bevel gears 130 and a clutch 131 which is operated by a cam 132. When the drive of the frame 61 is interrupted by the overrun device in the gear wheel 128, a stop pin 135 which can be moved by a cam 134 prevents the whirl-' ing head 60 rotating back'too far. On the side opposite the multi-grooved shaft 110, the frame 61 is of bifurcated construction, to form a counterweight 136 in order onthe one hand to compensate for the masses of those parts of the whirlinghead 60 which are at the top in FIG.3 and in order, on the other hand, to allow the finished and cut off spring to fall freely downwards.

A traction spring is produced as follows in the embodiment of FIG. 3:

The feed rolls 35 push the leading free end of the wire 29 into the clamping device 30. As soon as the whirling head 60 is moved by its drive, the guide rollers 1 l6 pivot against the supporting ring 133, which is oblique to the axis of the winding mandrel 121, and which causes a pitch of the spring corresponding to the thickness of the wire. -When the winding mandrel 121 has made approximately one-quarter of a revolution, the guide rolls 116 press against the spring wire 29 and thus press the winding mandrel 121 with the multiple groove shaft radially outwardly against the restoring force of the spring 115. At the upper dead center position of the crank transmission 28, the whirling head 60 is no longer driven, by virtue of the overrun device in the gear wheel 128, since the wound spring and the rearward end seek to relax, the whirling head 60 still runs somewhat in reverse. Such reverse movement is limited by a stop pin 135 through a cam 134. Once the whirling head 60 has stopped, the cut-offknife 32 cuts off the rear end of the spring, and after the guide rollers 116 have been pivoted outwards, the spring drops downwards and through the fifurcated counterweight 136 on the whirling head 60.

In an illustrated modified form of this whirling head 60, the guide rollers 116 may also be mounted on an axially displaceable central rod mounted in the pivot 122. This rod is preventedfrom rotating with respect to the pivot 122 by means of a spline. Axial displacement is brought about by an adjusting ring and a linkage actuated by a cam on the shaft 129.

It is possible for the nut 76in FIG. 2 to be driven through gear wheels by a central shaft mounted in the whirling head pivot 122 as in FIG. 3. If the rotary movement of this shaft is' initiated outside of the whirling head, through a rack such as rack 125 in FIG. 3, the end of the rack being provided with a roller which runs on an adjustable pitch straightedge, then any desired infinitely variable, pitch of the spring is possible if this pitch stra ightedge is jointly moved in synchronism by the crank transmission 28 in FIG. 3. In suchlast described construction, the guide rollers 116 which can be pivoted out and which produce the pitch in FIG. 3, and also the spring 115 and the supporting ring 133'are then eliminated.

FIG. 4 illustrates on a larger detail the modified 'whirling head 60 of the fourth embodiment; for the re-- mainder the machine of FIG. 4 conforms to the third embodiment, illustrated in FIG. 3. The winding mandrel used in FIG. 4 is constructed as a winding cylinder 140 which is rigidly connected to a gear wheel 141. The rotary movement of the frame 61 is transmitted through the gear wheels 112, 112, 114, bevel gears l l 1 and a toothed shaft 142, (which have already been de scribed with reference to FIG. 3,) to the gear wheel 141 and thus-to the winding cylinder 140. The gear wheel 141 with the winding cylinder 140 is mounted to be radially freely displaceable on a rod 150. Radial displacement is effected by the guide rollers 1 16 against the restoring force of the spring 115. The guide rollers 116 are here mounted on a fork member which can be pivoted out by means of a centrally mounted axially displaceable positioning rod 144 about an eccentrically v mounted pivot 143, i.e., about an axis parallel with the axis of the winding cylinder 140.

In all the machines described, the winding mandrels can be exchanged according to the spring diameters desired. Similarly, all gear wheel transmissions, crank drives and pitches of a pitch straightedge can be varied. When the winding mandrels are in each case mounted to pivot on the frame about an intermediate gear shaft parallel with the relevant longitudinal axis, the run-on point can be held on the axis of rotation of the frame without difficulty and even with different winding mandrel diameters. v If the pitch of the finished coil springs is to be greater than the pitch determined only by the thickness of the wire, then the spring wire is fed at an angle dJin all positions of rotation of the winding mandrel around the axis of rotation of the frame.

Although the invention is illustrated and described with reference to'a plurality of preferred embodiments thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a plurality of preferred embodiments, but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. Winding machine for producing coil springs, comprising a winding mandrel rotatable about its longitudinal axis and simultaneously displaceable in an axial direction, means on the mandrel for firmly clamping the free end of a spring wire, means for mounting said mandrel for additional rotation about a second axis at right anglesto its longitudinal axis, the second axis cutting the axis of the wire at the run-on point at which the incoming spring wire first touches the periphery of the winding mandrel, the second axis being disposed parallel with the tangent to the Winding mandrel at the runon point of the wire.

2. Winding machine according to claim 1, comprising a driveable frame which is rotatable about the second axis and on which the winding mandrel is rotatably disposed.

3. Winding machine according to claim 2, comprising a rotatable frame, a threaded spindle mounted on the frame transverse to the axis of rotation of the frame, the mandrel being disposed coaxial of the threaded spindle and having threaded engagement therewith, and means for positively rotating the mandrel when the frame rotates.

4. Winding machine according to claim 3, comprising means mounting the threaded spindle for rotation on the frame, the means for driving the threaded spindle comprising a drive train having serially connected gearing and a selectively engageable clutch.

5. Winding machine according to claim'2, wherein the winding mandrel has a threaded spindle coaxial thereof and rigidly connected thereto, a nut thr'eadedly receiving the threaded spindle, said nut being rotatably mounted in the frame against axial displacement, and

means for positiyely rotating the nut when the frame rotates.

6. Winding machine according to claim 5, wherein the means for positively rotating the nut when the frame rotates comprises a driving train including a selectively engagable clutch and gearing connected in series and extending between the nut and the frame.

7. Winding machine according to claim 2, wherein the winding mandrel is rotatable and is axially displaceably mounted on the frame, the winding mandrel being provided with a gearwheel which, upon rotation of the frame, can be positively driven through an intermediate gearing, and comprising an annular flange, a thrust spring clamped on the winding mandrel between a gearwheel of the intermediate gearing and the annular flange, an adjusting device for moving at least one guide roller between 21 released position for ejection of the completed coil spring and an operating position in which it presses the already formed spirals against the annular flange.

8. Winding machine according to claim 7, wherein the adjusting device has, for pivoting the guide roller, a shaft which describes the shell of a cone and which forms an angle with the axis of rotation of the frame.

9. Winding machine according to claim 2, wherein the winding mandrel is a winding cylinder which is rotatably and displaceably mounted on a rod mounted on the frame, the rod at one end carrying a gearwheel which, upon rotation of the frame, can be positively driven through an intermediate gearing and a shaft which has teeth meshing with the said gearwheel, between the gearwheel and a rotary bearing disposed on the frame, there being a thrust spring clamped on the rod, and an adjusting device for moving at least one guide roller between a release position for ejecting the completed coil spring and an operating position in which it presses the already formed spirals at least indirectly against the gearwheel which is being displaced on the rod.

10. Winding machine according to claim 9, wherein the adjusting device is constructed as an arrangement for pivoting the guide roller about an axis parallel with the axis of the winding cylinder.

11. Winding machine according to claim 6, wherein the nut is coupled through bevel gears to a shaft disposed coaxially of the axis of rotation of the frame, a pinion non-rotatably mounted on said shaft, said pinion meshing with a rack which carries at one end a rotatably mounted roller which rolls on a straight pitch straightedge which, driven by a crank drive, performs a stroke during the winding process.

12. Winding machine according to claim 3, wherein the winding mandrel is mounted on the frame so that it can swivel about a countershaft parallel with its longitudinal axis.

UNITED STATES PATENT OFFICE Page 1 of 2 CERTIFICATE OF CORRECTION PATENT NO. 3,807,211

DATE I April 30, 1974 INVENTOR(S) I Joachim Huhnen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below: O

Col. 1, line 66, change "sinding" to --winding--.

Col. 2, line 26, change "in" to --on--.

. line 27, after "63" insert line 50, after "gear" insert --portion--.

Col. 4, line 26, change "fifurcatedY' to --bifurcated-.

I In the drawings: Cancel Figure 3 of the drawing and substitute therefore the attached Figure 3.

Signed and Sealed this sixteenth Day of March 1976 [SEAL] Arrest:

' RUTH. C. MASON C. MARSHALL DANN I PSIHIS 11K" Commissioner ofParenrs and Trademarks Page 2 of 2 Patent No. 3,807,211 

1. Winding machine for producing coil springs, comprising a winding mandrel rotatable about its longitudinal axis and simultaneously displaceable in an axial direction, means on the mandrel for firmly clamping the free end of a spring wire, means for mounting said mandrel for additional rotation about a second axis at right angles to its longitudinal axis, the second axis cutting the axis of the wire at the run-on point at which the incoming spring wire first touches the periphery of the winding mandrel, the second axis being disposed parallel with the tangent to the winding mandrel at the run-on point of the wire.
 2. Winding machine according to claim 1, comprising a driveable frame which is rotatable about the second axis and on which the winding mandrel is rotatably disposed.
 3. Winding machine according to claim 2, comprising a rotatable frame, a threaded spindle mounted on the frame transverse to the axis of rotation of the frame, the mandrel being disposed coaxial of the threaded spindle and having threaded engagement therewith, and means for positively rotating the mandrel when the frame rotates.
 4. Winding machine according to claim 3, comprising means mounting the threaded spindle for rotation on the frame, the means for driving the threaded spindle comprising a drive train having serially connected gearing and a selectively engageable clutch.
 5. Winding machine according to claim 2, wherein the winding mandrel has a threaded spindle coaxial thereof and rigidly connected thereto, a nut threadedly receiving the threaded spindle, said nut being rotatably mounted in the frame against axial displacement, and means for positively rotating the nut when the frame rotates.
 6. Winding machine according to claim 5, wherein the means for positively rotating the nut when the frame rotates comprises a driving train including a selectively engagable clutch and gearing connected in series and extending between the nut and the frame.
 7. Winding machine according to claim 2, wherein the winding mandrel is rotatable and is axially displaceably mounted on the frame, the winding mandrel being provided with a gearwheel which, upon rotation of the frame, can be positively driven through an intermediate gearing, and comprising an annular flange, a thrust spring clamped on the winding mandrel between a gearwheel of the intermediate gearing and the annular flange, an adjusting device for moving at least one guide roller between a released position for ejection of the completed coil spring and an operating position in which it presses the already formed spirals against the annular flange.
 8. Winding machine according to claim 7, wherein the adjusting device has, for pivoting the guide roller, a shaft which describes the shell of a cone and which forms an angle with the axis of rotation of the frame.
 9. Winding machine according to claim 2, wherein the winding mandrel is a winding cylinder which is rotatably and displaceably mounted on a rod mounted on the frame, the rod at one end carrying a gearwheel which, upon rotation of the frame, can be positively driven through an intermediate gearing and a shaft which has teeth meshing with the said gearwheel, between the gearwheel and a rotary bearing disposed on the frame, there being a thrust spring clamped on the rod, and an adjusting device for moving at least one guide roller between a release position for ejecting the completed coil spring and an operating position in which it presses the already formed spirals at least indirectly against the gearwheel which is being displaced on the rod.
 10. Winding machine according to claim 9, wherein the adjusting device is constrUcted as an arrangement for pivoting the guide roller about an axis parallel with the axis of the winding cylinder.
 11. Winding machine according to claim 6, wherein the nut is coupled through bevel gears to a shaft disposed coaxially of the axis of rotation of the frame, a pinion non-rotatably mounted on said shaft, said pinion meshing with a rack which carries at one end a rotatably mounted roller which rolls on a straight pitch straightedge which, driven by a crank drive, performs a stroke during the winding process.
 12. Winding machine according to claim 3, wherein the winding mandrel is mounted on the frame so that it can swivel about a countershaft parallel with its longitudinal axis. 